Gruv Gear FUMP Bridge Muter (4-5 String Bass, Black) (FUMP5-BLK) Works best when string fingerboard setup has little to no radius Takes only a second to slide on or off, unlike the old cut foam solution Clips onto your strap or music stand when not in use Can be inserted from top or bottom Requires only a 1" (2.5 cm) of space between pickup and bridge